Improvement in surgical or dental operating-chairs



UNITED STATES PATENTA OFFICE.

M. VALDO HANOHETT, OF SYRAOUSE, NEIV YORK.

IMPROVEMENT IN SURGICAL OR DENTAL OPERATING-CHAIRS.

Specioation forming part of Letters Patent No. 5,711, dated August 15, 1848.

To @ZZ whom it may concern:

Be it known that I, M. WALDO HANcHnr'r, of Syracuse, in the county of Onondaga and State of New York, have invented a new and useful Improvement in Operating Chairs; and I do hereby declare the following to be a full, clear, and exact description of the construction and operation of the same, reference being had to the annexed drawings, making part of this specification.

To enable others to construct and use my invention, I will describe its construction and operation.

The nature of my invention consists in providing a more simple, durable, and convenient mode than has heretofore been used of adjusting the positions of chairs for convenience in dental and surgical operations or for other purposes.

In Constructing my chair I make the seat A, arms B, back C, and head-piece D in any of the known orvsconvenient forms. I then construct a base-work E, in the center of which is a standard F. The seat of the chair is connected with the standard by means of two curved cross-bars G and H. The bar G is attached to the sides of the chair-seat A by means of the hingejoints I and J at its ends and to the standard Fby means of the screw K, which projects down` ward from its center and passes through the center of its standard. A nut is placed within the standard, through which the screw works and serves to elevate or depress the chair at pleasure. The bar H is attached permanently to the front and back of the chairseat, and its Acurved part passes through a slot in the center of the bar G. A latch L is attached to the bar G in such a manner that it takes hold of the cogs or notches M, cut on the lower edge of the bar II. A clamp N is attached to the top of the standard F, which acts upon the screw K at pleasure7 preventing it from turning, and thereby holding the chair from turning on its center. I t-hen construct a foot-piece O, in any convenient form, and attach it to t-he base-work E by means of the curved bars or levers PP. The upper ends ofthese bars are attached to the footpiece O andthe other at a point between the foot-piece and chair. On. the front edge of the bars are notches into which the dog R falls and holds the foot-piece at any desired height. In consequence of the levers Pbeing attached to the basework at a point between the foot-piece and chair, it follows that the foot-piece will approach the chair at the same time that it is being elevated.

rIhe operation and purpose of my invention are as follows: The bar G- is held in its place by the screw K, and sustains the chair upon the standard, while the joints I and J at its extremities allow a free motion of the chair backward and forward. The bar II, being attached to the front and back of the chair-seat, passes freely through the center of the bar G and is held in any desired posisition by the latch L and cogs IWI. The chair may be elevated or depressed at pleasure by the screw K, and the clamp N may be used to fix it in any desired position..

v The object of elevating the foot-piece O, and at-the same time bringing it nearer the chair, is to adapt its position to persons of diierent heights.

The principal object of my invention is to vary the position of the chair and fooi-piece as may be desired, for convenience in dental and surgical operations, or for other purposes requiring similar apparatus.

Having thus fully described the manner in which I construct my chair and shown the operation of the respective pa-rts, what I claim therein as new, and desire to secure by Letters Patent, is

1. Themode herein vset forth of constructing, combining, and arranging the cross-bars G and H with their -respective parts-viz., in such a manner that the bar G will sustain the chair by hinge-joints at its extremities and rest upon the screw K at its center, and the curved bar lH will pass through a slot in the bar G or in the screw K and serve with the latch L, or any other device answering the same purpose, to hold the chair from falling backward at any degree of inclination, or any other mode substantially the same or analogous in its results.

2. The mode above described of elevating the foot-piece O-viz., in such a manner that it will approach the chair at the same time that it is being elevated.

M. VVALDO HANCHETT.

I'Vitnesses:

AMos WEs'rooTT, Tiros. D. WAsHBURN. 

